Oxazinoquinolonas useful for treating viral infections.

A compound of formula ** ** wherein R1 is C1-6alkyl, optionally substituted with -OH, -OC 1-4 alkyl or het; wherein C1-6 alkyl is optionally partially unsaturated; wherein het is a radical of a heterocyclic ring of 5 or 6 membered ring having one or two heteroatoms selected from the group consisting of oxygen, sulfur and N; or a salt, racemate, solvate, tautomer or pharmaceutically acceptable optical isomer.